Question 1

What can be counted as representing individual infectious virions from a phage suspension?

Accepted Answer

A)  plaques 
B)  viruses 
C)  genomes 
D)  proteomes 
E)  burst size 
A)  plaques 
B)  viruses 
C)  genomes 
D)  proteomes 
E)  burst size A

Question 2

The proteins found in animals and plants that can recognize general signs of viral infections are

Accepted Answer

A)  RNA interference. 
B)  interferons. 
C)  T-lymphocytes. 
D)  surface receptors. 
E)  antibodies. 
A)  RNA interference. 
B)  interferons. 
C)  T-lymphocytes. 
D)  surface receptors. 
E)  antibodies. B

Question 3

What is the advantage of symmetry in viral particles?

Accepted Answer

Symmetry provides a way to form a package out of repeating protein units. This requires a small number of genes, since the same protein unit is repeated. Viral genomes are generally very small, so they have few genes. They can also devote more resources to copying their genome for viral replication if it takes few resources to make the capsid proteins.

Question 4

Hershey & Chase (1952) showed that the transmission of DNA by a bacteriophage to a host cell led to the production of progeny bacteriophages. What did this confirm?

Accepted Answer

A)  DNA is the hereditary material. 
B)  Viruses can infect bacteria. 
C)  Phage genomes can integrate into a bacterial genome. 
D)  Phages inject their genome through the cell envelope. 
E)  Various host molecules can serve as a phage receptor. 
A)  DNA is the hereditary material. 
B)  Viruses can infect bacteria. 
C)  Phage genomes can integrate into a bacterial genome. 
D)  Phages inject their genome through the cell envelope. 
E)  Various host molecules can serve as a phage receptor.

Question 5

Which filamentous virus causes a fatal disease in humans and is also related to primates?

Accepted Answer

A)  HIV 
B)  Ebola 
C)  smallpox 
D)  cowpox 
E)  herpes virus 
A)  HIV 
B)  Ebola 
C)  smallpox 
D)  cowpox 
E)  herpes virus

Question 6

The RNA genome of the potato spindle tuber viroid requires which type of modified host polymerase for replication?

Accepted Answer

A)  DNA-dependent DNA polymerase 
B)  DNA-dependent RNA polymerase 
C)  RNA-dependent DNA polymerase 
D)  RNA-dependent RNA polymerase 
E)  reverse transcriptase 
A)  DNA-dependent DNA polymerase 
B)  DNA-dependent RNA polymerase 
C)  RNA-dependent DNA polymerase 
D)  RNA-dependent RNA polymerase 
E)  reverse transcriptase

Question 7

What is it necessary for bacteriophage and animal virus entry into a cell? How does that differ from plant viral entry?

Accepted Answer

There is a specific receptor on the host

Question 8

What type of diseases are unique in that they can be transmitted by an infective protein that propagates conformational change of existing molecules without synthesizing entirely new infective molecules?

Accepted Answer

A)  viral 
B)  viroid 
C)  bacterial 
D)  virion 
E)  prion 
A)  viral 
B)  viroid 
C)  bacterial 
D)  virion 
E)  prion

Question 9

Which of the following is FALSE concerning HIV?

Accepted Answer

A)  It is the causative agent of AIDS. 
B)  It makes a DNA copy of its RNA genome. 
C)  Reverse transcriptase is translated from an early gene. 
D)  The virion contains two copies of the HIV genome. 
E)  The viral RNA is copied into double-stranded DNA. 
A)  It is the causative agent of AIDS. 
B)  It makes a DNA copy of its RNA genome. 
C)  Reverse transcriptase is translated from an early gene. 
D)  The virion contains two copies of the HIV genome. 
E)  The viral RNA is copied into double-stranded DNA.

Question 10

When a bacterial cell is infected, the virus protection coat

Accepted Answer

A)  enters the host cell with the viral genome. 
B)  remains on the outside of the host cell. 
C)  enters the host cell separately from the viral genome. 
D)  is released to attach to and inject another host cell. 
E)  becomes part of the host cell membrane. 
A)  enters the host cell with the viral genome. 
B)  remains on the outside of the host cell. 
C)  enters the host cell separately from the viral genome. 
D)  is released to attach to and inject another host cell. 
E)  becomes part of the host cell membrane.

Question 11

Why was the advent of tissue culture heralded as the end of the "monkey era"? What types of things are we able to do with it?

Accepted Answer

Monkeys were being used to culture polio

Question 12

Why are viruses not affected by antibiotics? Why are there so few antiviral drugs?

Accepted Answer

Viruses are not cellular entities. Commo

Question 13

Which of the following is INCORRECT about a virus?

Accepted Answer

A)  It may cause human pneumonia. 
B)  It may be as large as some bacteria. 
C)  It conducts DNA repair. 
D)  It conducts protein folding by chaperones. 
E)  It is a cellular particle. 
A)  It may cause human pneumonia. 
B)  It may be as large as some bacteria. 
C)  It conducts DNA repair. 
D)  It conducts protein folding by chaperones. 
E)  It is a cellular particle.

Question 14

In bacteriophage T4, the DNA genome is contained in the head, and binding to the host is facilitated by attachment of the

Accepted Answer

A)  capsid. 
B)  neck. 
C)  tail fibers. 
D)  envelope. 
E)  tegument. 
A)  capsid. 
B)  neck. 
C)  tail fibers. 
D)  envelope. 
E)  tegument.

Question 15

To count the number of viruses in a solution, one can perform a plaque assay. Describe how a plaque is generated in the case of a lytic virus and how a virus that does not lyse its host can be detected.

Accepted Answer

A plaque represents the area where one v

Question 16

Within a host, receptor molecules can also determine the ________, or tendency to infect a particular tissue type.

Accepted Answer

A)  tropism 
B)  host range 
C)  virulence 
D)  burst size 
E)  plaque 
A)  tropism 
B)  host range 
C)  virulence 
D)  burst size 
E)  plaque

Question 17

If something descended from a common ancestor, it is

Accepted Answer

A)  monomeric. 
B)  monophyletic. 
C)  monogrammed. 
D)  monosyllabic. 
E)  monolithic. 
A)  monomeric. 
B)  monophyletic. 
C)  monogrammed. 
D)  monosyllabic. 
E)  monolithic.

Question 18

The proteomic tree of bacteriophages is based on comprehensive analysis of viral

Accepted Answer

A)  DNAs. 
B)  RNAs. 
C)  proteins. 
D)  capsids. 
E)  host ranges. 
A)  DNAs. 
B)  RNAs. 
C)  proteins. 
D)  capsids. 
E)  host ranges.

Question 19

The primary factor determining the life cycle of an animal virus is the physical form of the

Accepted Answer

A)  envelope. 
B)  capsid. 
C)  genome. 
D)  receptor. 
E)  burst. 
A)  envelope. 
B)  capsid. 
C)  genome. 
D)  receptor. 
E)  burst.

Question 20

Dysbiosis is the result of

Accepted Answer

A)  deterioration of health due to loss of bacteria. 
B)  increase in health due to loss of bacteria. 
C)  host bacterium undergoing a lytic cycle. 
D)  host bacterium undergoing a lysogenic cycle. 
E)  slow release. 
A)  deterioration of health due to loss of bacteria. 
B)  increase in health due to loss of bacteria. 
C)  host bacterium undergoing a lytic cycle. 
D)  host bacterium undergoing a lysogenic cycle. 
E)  slow release.

Exam 6: Viruses

What can be counted as representing individual infectious virions from a phage suspension?

The proteins found in animals and plants that can recognize general signs of viral infections are

What is the advantage of symmetry in viral particles?

Hershey & Chase (1952) showed that the transmission of DNA by a bacteriophage to a host cell led to the production of progeny bacteriophages. What did this confirm?

Which filamentous virus causes a fatal disease in humans and is also related to primates?

The RNA genome of the potato spindle tuber viroid requires which type of modified host polymerase for replication?

What is it necessary for bacteriophage and animal virus entry into a cell? How does that differ from plant viral entry?

What type of diseases are unique in that they can be transmitted by an infective protein that propagates conformational change of existing molecules without synthesizing entirely new infective molecules?

Which of the following is FALSE concerning HIV?

When a bacterial cell is infected, the virus protection coat

Why was the advent of tissue culture heralded as the end of the "monkey era"? What types of things are we able to do with it?

Why are viruses not affected by antibiotics? Why are there so few antiviral drugs?

Which of the following is INCORRECT about a virus?

In bacteriophage T4, the DNA genome is contained in the head, and binding to the host is facilitated by attachment of the

To count the number of viruses in a solution, one can perform a plaque assay. Describe how a plaque is generated in the case of a lytic virus and how a virus that does not lyse its host can be detected.

Within a host, receptor molecules can also determine the ________, or tendency to infect a particular tissue type.

If something descended from a common ancestor, it is

The proteomic tree of bacteriophages is based on comprehensive analysis of viral

The primary factor determining the life cycle of an animal virus is the physical form of the

Dysbiosis is the result of

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

Filters